Virtual Production 101: The Three Vis's (Previs, Techvis, Postvis)

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(5 minute read)

In chapter two of our virtual production series, we examine the three types of "Vis" in modern filmmaking: Previs, Techvis, and Postvis.

From Jurassic World (2015) IMDb Photo

Jurassic World: Fallen Kingdom (2018)


What is it?

Previs, short for pre-visualization, is a filmmaker's way of seeing his movie before the actual shoot. Another way to describe it is as a virtual storyboard, where artists create short animated video clips to visualize what the story would roughly look like on camera. Large CGI projects like Harry Potter or Star Wars, which have a lot of visual effects, would most likely use Previs to pre-screen most of their battle scenes and magical creatures before they move on to production.

If Previs answers the 'What?', Techvis would answer the 'How?'. Short for technical visualization (90% sure about that), Techvis is focused on the camerawork and all the technical aspects and measurements that surround shooting your story. It's important for prepping special effects because it requires a lot of setup to make sure the camera captures everything it needs during production before it gets brought to life in Post.

Postvis, or post-visualization, is the culmination of Previs and Techvis because it's what you end up seeing on screen. Interestingly, Postvis doesn't always take place in a dark room where the editor nerds go and do their incredible work. More production sets now have editors on location to render the CG effects right after or during shoots. This allows the director to quickly see the close-to final product and make executive decisions during production.

How does it look? 

I think Proof, Inc. does an exemplary job summarizing all 3 virtual production pieces. Highly recommend checking out their website:

The Fate of the Furious (2017)

This YouTube video is also useful, taking us behind the scenes of Jurassic World: Fallen Kingdom.


Jurassic World: Fallen Kingdom TechVis Sizzle Reel | Proof Inc

What are some of the needed Materials?

  • Virtual camera motion tracking systems
  • Green Screens
  • Measuring Tools
    • Ruler/Tape Measure (literally)
    • Speedometer
  • 3-D Animation software
  • Compositing software - to merge images and video together e.g. actors performing in front of a green screen

Quotes

“It usually takes between two weeks and a month for the asset builders to create all the pieces we need to start our previs. And that work continues for assets that appear later.”
~ Nick Markel, Previs Supervisor for The Avengers

"Rian wanted to explore what it would look like to push down onto the planet past the rebel ships evacuating and asked our postvis artists to visualize this.” 
~ Barry Howell, Postvis Supervisor for The Last Jedi

"Our general contribution on this film was techvis and technical planning, which I did while being onset to help plan shooting for the zero-gravity sequences."
~ Casey Schatz Virtual Production Supervisor for The Martian

Examples and Resources